Please help with 17-18

Which expression is equivalent to 5r6141 2r+st6

From the beginning of the day the temperature rose 15 degrees so that by 4 pm it was 87 degrees. what was the temperature at the start of the day

In the diagram, be and ad pass throughthe center of circle o, and the area ofsector aoc is 47.45 square units. what isthe area of sector boc? use the value =3.14, and round your answer to two decimalplaces.22.33 square units25.12 square units